Mining magnate Gina Rinehart says Rio Tinto should move its headquarters from London to Perth now that iron ore boss Sam Walsh has been appointed as the miner's new CEO.

In a statement to Fairfax Media Rinehart said most of Rio's money was generated in WA and it made sense for the company to set up in Perth.

“In congratulating Sam on his promotion to such an important position within Rio Tinto, we have urged him to take this opportunity and also move the Rio Tinto headquarters from London to Perth where given most of Rio Tinto's revenue is generated in Australia, it logically belongs,” she said.

Last week Rio released its December quarter results and revealed its WA iron ore assets accounted for more than 70 per cent of the company's annual earnings.

Rinehart also urged Walsh to pour more investment into Australia after shareholders had seen “much diminution in value via investments in risky countries”.

A long-time opponent of the mining tax and carbon tax, Rinehart also called on Walsh and Rio Tinto to join the fight against Government initiatives that she claimed were “diminishing cost competitiveness”.

She also urged the company to focus on expanding the Hope Downs iron ore project, which is party mined under a 50:50 joint venture with Rio and Hancock.

According to Fairfax Media Rinehart said three deposits within the Hope Downs precinct – Baby Hope, Hope 2, and Hope 5 – were “convenient for early development”.